by Clare Wilson AS MANY as 1 in 10 cases of schizophrenia may be triggered by an autoimmune reaction against brain cells, according to early trial results shared with New Scientist. The finding offers the possibility of gentler treatments for this devastating mental illness. Last month, doctors at a conference at the Royal Society of Medicine in London were told to consider an autoimmune cause when people first show symptoms of schizophrenia. People with schizophrenia experience symptoms of psychosis, such as hallucinations, delusions and paranoia. It affects 1 per cent of people in the West and is thought to be caused by overactive dopamine signalling pathways in the brain. Anti-psychotic drugs don't always work wellMovie Camera and have serious side effects. Previous studies had found that antibodies that target the NMDA receptor on neurons trigger brain inflammation, leading to seizures, comas – and sometimes psychosis (Annals of Neurology, doi.org/fdgnpc). In the past few years, these antibodies have also been found in the blood of people whose only symptom is psychosis. In 2010, Belinda Lennox at the University of Oxford tested 46 people with recent onset of psychosis for antibodies known to target neurons. Three people – about 6 per cent – tested positive (Neurology, doi.org/chs532). "The question is whether a larger percentage of cases might have other antibodies which we cannot yet detect," says Robin Murray at the Institute of Psychiatry in London, who wasn't involved in the research. Now Lennox is conducting a larger trial. Early results suggest other antibodies could well be involved. © Copyright Reed Business Information Ltd.

Keyword: Schizophrenia; Neuroimmunology
Link ID: 19251 - Posted: 02.15.2014

Ian Sample, science correspondent, in Chicago Researchers have found evidence – if evidence were needed – that men have less sex after becoming a father for the first time. A study of more than 400 young men in the Philippines found that their sex lives declined significantly when they had their first child. The fall in sexual activity was associated with the men's testosterone levels, which are known to fall when men start families, but the latest research shows that the greater the fall in testosterone, the less sex men reported. Lee Gettler, an anthropologist at the University of Notre Dame in Indiana, gathered medical and lifestyle information on the men from the ages of 21 to 26 years old and found there were physiological and behavioural changes as some of them married and had children. When men got married their testosterone levels fell, and declined even further when they had their first child. That led to the question of whether falling testosterone might impact on their sex lives. "I didn't think that testosterone would be linked to men's sexual behaviour, but when we tested it we found that as men transitioned to fatherhood, the more their testosterone declined the less frequently they reported having sex with their partner," Gettler said. "Does this mean that men who care for children have low testosterone and no sex? No, it has nothing to do with childcare." The impact on men's sex lives was not linked to the amount of time and energy they invested in childcare, he said. Gettler described his research at the annual meeting of the American Association for the Advancement of Science in Chicago. © 2014 Guardian News and Media Limited

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 19250 - Posted: 02.15.2014

CHICAGO, ILLINOIS—Chances are, your baby won’t respond to questions like, “How was your day, honey?” Or, “What do you want to be when you grow up?” But just because infants can’t form sentences until toddlerhood doesn’t mean that they don’t benefit from early conversations with their parents. It’s long been observed that the better children perform in school and the more successful their careers, the higher the socioeconomic status (SES) of their family—and, according to Stanford University’s Anne Fernald, this has a lot to do with how parents of different SES speak to their babies. Those babies that are spoken to frequently in an engaging and nurturing way—generally from a higher SES—tend to develop faster word-processing skills, or the ability to follow a sentence from one object or setting to another. This word processing speed, in turn, directly relates to the development not just of vocabulary and language skills, but also memory and nonverbal cognitive abilities. In a new study, Fernald and colleagues measured parent-baby banter from round-the-clock recordings in babies’ homes, then tested those babies’ word-processing speed using retinal-following experiments that tracked how long it took them to follow a prompt to an image like a dog or juice. The researchers found that the differences in word-processing speed between high and low SES were stark: By 2 years of age, high SES children were 6 months ahead of their low SES counterparts; and by age 3, the differences in processing abilities were highly predictive of later performance in and out of school, the team reported here today at the annual meeting of AAAS, which publishes Science. Fernald hopes that this research will lead to interventions that help to shrink the language gap between kids on either side of the income gap. © 2014 American Association for the Advancement of Science

Keyword: Development of the Brain; Language
Link ID: 19249 - Posted: 02.15.2014

by Laura Sanders Some of the human brain’s wrinkles are forged by the behavior of a single gene, scientists report in the Feb. 14 Science. By scanning more than 1,000 people’s brains, researchers identified five with malformed wrinkles in a specific region. The abnormalities — numerous shallow dips surrounding an unusually wide brain furrow called the Sylvian fissure — were linked with intellectual and language disabilities and seizures in these people. All five people had mutations that dampened the behavior of a gene named GPR56. Curbing this gene’s behavior results in diminished production of cells that eventually become neurons in the affected brain region, mouse experiments revealed. Boosting the gene’s behavior had the opposite effect. The results might clarify how wrinkles allow human brains to cram lots of neurons into a small space, Christopher Walsh of Boston Children’s Hospital and colleagues suggest. © Society for Science & the Public 2000 - 2013

Keyword: Development of the Brain; Genes & Behavior
Link ID: 19248 - Posted: 02.15.2014

Katherine Sharpe Ben Harkless could not sit still. At home, the athletic ten-year-old preferred doing three activities at once: playing with his iPad, say, while watching television and rolling on an exercise ball. Sometimes he kicked the walls; other times, he literally bounced off them. School was another story, however. Ben sat in class most days with his head down on his desk, “a defeated heap”, remembers his mother, Suzanne Harkless, a social worker in Berkeley, California. His grades were poor, and his teacher was at a loss for what to do. Harkless took Ben to a therapist who diagnosed him with attention deficit hyperactivity disorder (ADHD). He was prescribed methylphenidate, a stimulant used to improve focus in people with the condition. Harkless was reluctant to medicate her child, so she gave him a dose on a morning when she could visit the school to observe. “He didn't whip through his work, but he finished his work,” she says. “And then he went on and helped his classmate next to him. My jaw dropped.” ADHD diagnoses are rising rapidly around the world and especially in the United States, where 11% of children aged between 4 and 17 years old have been diagnosed with the disorder. Between half and two-thirds of those are put on medication, a decision often influenced by a child's difficulties at school. And there are numerous reports of adolescents and young adults without ADHD using the drugs as study aids. © 2014 Nature Publishing Group,

Keyword: ADHD; Learning & Memory
Link ID: 19247 - Posted: 02.13.2014

By James Gallagher Health and science reporter, BBC News Brain scans show a complex string of numbers and letters in mathematical formulae can evoke the same sense of beauty as artistic masterpieces and music from the greatest composers. Mathematicians were shown "ugly" and "beautiful" equations while in a brain scanner at University College London. The same emotional brain centres used to appreciate art were being activated by "beautiful" maths. The researchers suggest there may be a neurobiological basis to beauty. The likes of Euler's identity or the Pythagorean identity are rarely mentioned in the same breath as the best of Mozart, Shakespeare and Van Gogh. The study in the journal Frontiers in Human Neuroscience gave 15 mathematicians 60 formula to rate. One of the researchers, Prof Semir Zeki, told the BBC: "A large number of areas of the brain are involved when viewing equations, but when one looks at a formula rated as beautiful it activates the emotional brain - the medial orbito-frontal cortex - like looking at a great painting or listening to a piece of music." The more beautiful they rated the formula, the greater the surge in activity detected during the fMRI (functional magnetic resonance imaging) scans. "Neuroscience can't tell you what beauty is, but if you find it beautiful the medial orbito-frontal cortex is likely to be involved, you can find beauty in anything," he said. To the the untrained eye there may not be much beauty in Euler's identify, but in the study it was the formula of choice for mathematicians. BBC © 2014

Keyword: Emotions; Attention
Link ID: 19246 - Posted: 02.13.2014

|By Dina Fine Maron Concussions are a major problem in football. But brain injury is a growing concern in soccer, too, usually resulting from heading the ball or collisions. A meta-analysis of existing studies finds that concussions accounted for between 6 and 9 percent of all injuries sustained on soccer fields. Most of those concussions come from when two players make for the ball, often when a player’s elbow, arm or hand inadvertently makes contact with another player’s head. But we’re not just talking about injuries to professionals. One work shows some 63 percent of all varsity soccer players have sustained concussions—yet only 19 percent realized it. And another says girls’ soccer can be particularly brutal, accounting for 8 percent of all sports-related concussions among high school girls. The findings are in the journal Brain Injury. [Monica E. Maher et al., Concussions and heading in soccer: A review of the evidence of incidence, mechanisms, biomarkers and neurocognitive outcomes] Professional players who reported a great deal of extensive heading the ball during their careers did the poorest in tests of verbal and visual memory compared with other players. Goalies and defenders were most likely to get concussions. So if you want to bend it like Beckham, maybe focus on playing midfield or offense. Padding the goal posts would also be a heads-up policy. © 2014 Scientific American

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 19245 - Posted: 02.13.2014

By Ben Cimons, Recently I received an e-mail from my mother with a link to the harrowing tale of a 16-year-old Northern Virginia girl who overdosed on heroin and died, and whose companions had dumped her body. My mom wrote that she found the story “terrifying, because that easily could have been you. I thank God every day that it wasn’t, and that you are safe and healthy.’’ She was right. It could have been me, and it very nearly was. The only difference was that after I passed out from an accidental heroin overdose, the person I was with called 911 before abandoning me. Today I am 23 years old, living in a recovery house in Wilmington, N.C., and slowly regaining my life. But it has not been easy. Heroin is seductive. The minute it hits you, all your worries disappear. You are content with everything. You feel warm. You can’t help but smile. You feel free. The first time I tried it, I found an escape from the feelings of sadness and isolation I had been experiencing for as long as I could remember. But once heroin gets a hold on you, it never lets go. Heroin has been in the news a lot lately, most recently because of the death, apparently by overdose, of actor Philip Seymour Hoffman. Heroin is everywhere. It’s easy to find, including in the suburbs where I lived until recently, and cheaper than prescription pills. © 1996-2014 The Washington Post

Keyword: Drug Abuse
Link ID: 19244 - Posted: 02.13.2014

by Bethany Brookshire There are times when science is a painful experience. My most excruciating moment in science involved a heated electrode placed on my bare leg. This wasn’t some sort of graduate school hazing ritual. I was a volunteer in a study to determine how we process feelings of pain. As part of the experiment I was exposed to different levels of heat and asked how painful I thought they were. When the electrode was removed, I eagerly asked how my pain tolerance compared with that of others. I secretly hoped that I was some sort of superwoman, capable of feeling pain that would send other people into screaming fits and brushing it off with a stoic grimace. It turns out, however, that I was a bit of a wuss. Ouch. I figured I could just blame my genes. About half of our susceptibility to pain can be explained by genetic differences. The other half, however, remains up for grabs. And a new study published February 4 in Nature Communications suggests that part of our susceptibility to pain might lie in chemical markers on our genes. These “notes” on your DNA, known as epigenetic changes, can be affected by environment, behavior and even diet. So the findings reveal that our genetic susceptibility to pain might not be our destiny. Tim Spector and Jordana Bell, genetic epidemiologists at King’s College London, were interested in the role of the epigenome in pain sensitivity. Epigenetic changes such as the addition (or subtraction) of a methyl group on a gene make that gene more or less likely to be used in a cell by altering how much protein can be made from it. These differences in proteins can affect everything from obesity to memory to whether you end up like your mother. © Society for Science & the Public 2000 - 2013.

Keyword: Pain & Touch; Epigenetics
Link ID: 19243 - Posted: 02.12.2014

By Roy H. Hamilton and Jihad Zreik It's hard to imagine anyone, no matter how brilliant, who doesn't yearn to be even smarter. Thanks to recent advances in neural science, that wish may come true. Researchers are finding ways to rev up the human brain like never before. There would be just one question: Do we really want to inhabit that world? It may be too late to ask. Modern society has already embraced the basic idea of fine-tuning our intellects via artificial procedures—what might be termed “cosmetic” neurology. Schoolchildren take Adderall, Concerta and other attention-focusing medications. Parents and teachers rely on antidepressants and antianxiety drugs. And self-help books offer the latest advances in neuroscience to help ordinary people think faster and sharper. Add to those advances another cognitive-enhancement method: transcranial direct-current stimulation (tDCS). With this technique, electrodes applied to the scalp deliver minuscule amperages of current to the brain. This trickle of electricity seems to cause incremental adjustments in the electrical potentials of membranes in the neurons closest to the electrodes, increasing or decreasing their likelihood of firing. And that, in turn, induces measurable changes in memory, language, mood, motor function, attention and other cognitive domains. Investigators still aren't sure whether tDCS can cause long-term neural changes. Although most tests show only transient effects, there is limited evidence that repeated applications might have more persistent results. The procedure is not approved by the U.S. Food and Drug Administration, and the consensus among experts is that it should be performed only under qualified supervision. Nevertheless, if used properly, it is safe, portable, easy to implement and inexpensive. © 2014 Scientific American

Keyword: Intelligence; Robotics
Link ID: 19242 - Posted: 02.12.2014

By SINDYA N. BHANOO Mosquito sperm have a sense of smell, researchers are reporting, in a finding that could suggest ways to help control the spread of disease-carrying insects. The sperm carries a set of chemical sensors identical to the olfactory receptors on the mosquitoes’ antennas, according to a study in Proceedings of the National Academy of Sciences. Mosquitoes mate just once in their lifetime, and the female stores the male’s sperm in an organ called a spermatheca. Before the eggs mature, the female seeks out blood using the receptors on her antennas. Soon after, chemical signals cause the sperm tails to beat rapidly and start the fertilization process. “The sperm may need a chemical signal to become ready for fertilization,” said Jason Pitts, a researcher at Vanderbilt University and an author of the study, which was supported by the Gates Foundation as part of its efforts to improve global health. Another author, Laurence Zwiebel, also a Vanderbilt researcher, called the dual use of the olfactory receptors a clear and clever example of convergent evolution: The mosquitoes, he said, “found something that works and use it in multiple ways.” The scientists think olfactory receptors may exist on the sperm of many other insects, and they are developing chemical compounds that can be applied to breeding grounds to block the receptors. “You can effectively confuse the sperm or make them inactive,” Dr. Zwiebel said. © 2014 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 19241 - Posted: 02.12.2014

By Caitlin Kirkwood Glorious, refreshing sleep is eluding the majority of Americans. According to the National Sleep Foundation’s 2013 International Bedroom Poll 56 percent of people between the ages of 25 and 55 get an insufficient amount of sleep on workdays. On non-workdays individuals are then more likely to oversleep. They spend an additional 45 minutes catching Z’s in an attempt to compensate for accrued workweek sleep debt. Why are we constantly playing sleep-catch up during free time? As a society we are socially jet lagged. Social jet lag is the difference betweensleep patterns on work days and free days. These inconsistent sleeping habits result in sleep loss that is reminiscent of flying west across several time zones every Friday evening and traveling back East come Monday morning. The pattern reveals a critical disparity between society-imposed obligations, like work and family commitments, and our innate biological clock. Social jet lag might not sound like a big deal. What’s an hour or two of sleep lost here and there? But the chronic misalignment between our social and biological clocks is wreaking havoc on our health. Large-scale epidemiological studies have pointed a finger at short sleep duration for it’s causative role in the nationwide obesity crisis. When you get too little sleep, normal levels of appetite hormones are altered in a way that could lead to increased food consumption and weight gain. Unfortunately for people struggling with social jet lag, short sleep duration comes with the territory of the workweek. Some data even suggest that for every hour the biological clock is offset from the social clock, the chances of being overweight shoot-up by a whopping 33 percent. And supersizing the body mass index isn’t the only problem. Social jet lag has also been linked to the increased likelihood of nicotine and alcohol use, which independently contribute to additional health problems. © 2014 Scientific American

Keyword: Sleep
Link ID: 19240 - Posted: 02.12.2014

It seems simple: People are more likely to cooperate if everyone plays fair. But a new study suggests that fairness itself arises from an unlikely source: spite. Researchers made a mathematical model based on the so-called ultimatum game. In it, two players are offered a reward, and the first player makes an offer for how it should be split up. If the second player agrees, then they divide it accordingly. But if the second player refuses, then neither gets the reward. As shown in the image above, depending on the interaction of the players, the outcome can be classified as altruism, cooperation, selfishness, or spite. Previous experiments have shown that, over multiple rounds of the game, a culture of cooperation evolves where everyone makes fair offers. But the new study, published online today in the Proceedings of the Royal Society B, finds that when players start out using multiple different strategies, by making fair or unfair offers, and rejecting or accepting unfair offers, some will act out of spite. These spiteful players deny the first player the reward at a cost to himself. The calculations further show that the antisocial behavior will eventually cause fairness to become the most successful option, because there is no reason to reject a fair offer. In essence, fairness evolves in spite of spite, when players start out using different strategies. Though they warn against generalizing to humans, the researchers point out that if fairness is the basis for a moral society, then paradoxically, spite may have played a role in the evolution of morality. © 2014 American Association for the Advancement of Science.

Keyword: Emotions; Evolution
Link ID: 19239 - Posted: 02.12.2014

By JOHN LA PUMA SANTA BARBARA, Calif. — A FUNNY thing has happened in the United States over the last few decades. Men’s average testosterone levels have been dropping by at least 1 percent a year, according to a 2006 study in The Journal of Clinical Endocrinology and Metabolism. Testosterone appears to decline naturally with aging, but internal belly fat depresses the hormone further, especially in obese men. Drugs like steroids and opiates also lower testosterone, and it’s suspected that chemicals like bisphenol A (or BPA, commonly found in plastic food containers) and diseases like Type 2 diabetes play a role as well. Men feel the loss. Clinical testosterone deficiency, which is variously defined as lower than 220 to 350 nanograms of testosterone per deciliter of blood serum, can cause men to lose sex drive and fertility. Their bone density often declines, and they may feel tired and experience hot flashes and sweats. But “low T,” as the condition has been labeled, isn’t nearly as common as the drug ads for prescription testosterone would have you believe. Pharmaceutical companies have seized on the decline in testosterone levels as pathological and applicable to every man. They aim to convince men that common effects of aging like slowing down a bit and feeling less sexual actually constitute a new disease, and that they need a prescription to cure it. This is a seductive message for many men, who just want to feel better than they do, and want to give it a shot, literally. The problem is that prescription testosterone doesn’t just give your T level a boost: it may also increase your risk of heart attack. It can add huge numbers of red blood cells to your bloodstream and shrink your testes. In some men, it increases aggression and irritability. © 2014 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 19238 - Posted: 02.11.2014

by Laura Sanders A new analysis of cows shows that mamas make more milk for daughters. Other studies have hinted that human moms produce different milk for sons than for daughters, so perhaps lactating women also boost production for daughters. I love eavesdropping on people’s overly detailed coffee orders. You, sir, with the temerity to order a skinny split quad shot latte no whip no foam, with a side of lemon? Your extreme customizing just made my day. Such personalization was running through my mind as I read a recent study on cows. It turns out that another beverage is also subject to the specific, exacting standards of its drinker: milk. And the customer’s bossy demands seem to start before he or she is born. Heifers produce more milk for daughters than sons, Katie Hinde and colleagues report February 3 in PLOS ONE. When a cow gives birth to her first female, she makes about 1.6 percent more milk than she would have for a son, Hinde and colleagues found by analyzing the dairy records from a million and a half cows. And because calves born at dairy farms are taken away from their mothers soon after birth, the female calves’ requests to “make me more milk” must have come during pregnancy. Another interesting finding: The first pregnancy had an outsized effect on the cow’s future milk production. Cows that had sons first saw a slight bump in production when they got pregnant with a daughter, but didn’t catch up to the cows that had a daughter followed by a son. The first born daughter set the mom’s milk-making machinery on high, and that’s where it stayed for subsequent pregnancies. © Society for Science & the Public 2000 - 2013

Keyword: Sexual Behavior
Link ID: 19237 - Posted: 02.11.2014

|By Annie Sneed Alzheimer’s disease is now the sixth leading cause of death in the U.S., but researchers still do not know what causes the degenerative neurological disorder. In recent years they have pinpointed several genes that seem largely responsible for those cases in which the disorder develops early on, prior to age 60. They have also identified about 20 genes that can increase or decrease risk for the more common late-onset variety that starts appearing in people older than 60. But genetics simply cannot explain the whole picture for the over five million Americans with late-onset Alzheimer’s. Whereas genetics contribute some risk of developing this version of the disorder, no combination of genes inevitably leads to the disease. Scientists are now urgently searching for the other missing pieces to explain what causes late-onset Alzheimer’s. Some researchers have shifted their attention from genes to the environment—especially to certain toxins. Their studies of pesticides, food additives, air pollution and other problematic compounds are opening a new front in the battle against this devastating malady. Here’s a roundup of some of the possibilities being studied: Scientists have already found a strong potential link between pesticides and Parkinson’s disease. Now, a preliminary study released in January suggests that the pesticide DDT, which degrades so slowly that it continues to linger in the environment more than 40 years after the U.S. Environmental Protection Agency banned its use in the U.S., may also contribute to Alzheimer’s. © 2014 Scientific American

Keyword: Alzheimers; Neurotoxins
Link ID: 19236 - Posted: 02.11.2014

By DEBORAH SONTAG HUDSON, Wis. — Karen Hale averts her eyes when she drives past the Super 8 motel in this picturesque riverfront town where her 21-year-old daughter, Alysa Ivy, died of an overdose last May. She has contemplated asking the medical examiner, now a friend, to accompany her there so she could lie on the bed in Room 223 where her child’s body was found. But Ms. Hale, 52, is not ready, just as she is not ready to dismantle Ms. Ivy’s bedroom, where an uncapped red lipstick sits on the dresser and a teddy bear on the duvet. The jumble of belongings both comforts and unsettles her — colorful bras, bangle bracelets and childhood artwork; court summonses; a 12-step bible; and a Hawaiian lei, bloodstained, that her daughter used as a tourniquet for shooting heroin into her veins. “My son asked me not to make a shrine for her,” Ms. Hale said. “But I don’t know what to do with her room. I guess on some level I’m still waiting for her to come home. I’d be so much more empathetic now. I used to take it personal, like she was doing this to me and I was a victim.” When the actor Philip Seymour Hoffman died with a needle in his arm on Feb. 2, Ms. Hale thought first about his mother, then his children. Few understand the way addiction mangles families, she said, and the rippling toll of the tens of thousands of fatal heroin and painkiller overdoses every year. Perhaps it took Mr. Hoffman’s death, she said, to “wake up America to all the no-names who passed away before him,” leaving a cross-country trail of bereavement. © 2014 The New York Times Company

Keyword: Drug Abuse
Link ID: 19235 - Posted: 02.11.2014

Eighteen neurological patients in North Carolina may have been exposed to an incurable and fatal disorder similar to "mad cow" disease while undergoing surgery at the Novant Health Forsyth Medical Center because surgical instruments were insufficiently sterilized, the hospital said on Monday. Surgeons operated on the 18 patients on January 18 using tools that had not been sufficiently sanitized after they were used on a man suspected of having Creutzfeldt-Jakob Disease (CJD), the hospital in Winston-Salem said in a press statement. "On behalf of the entire team at Novant Health, I apologize to the patients and their families for having caused this anxiety," Jeff Lindsay, president of the medical center, said at a news conference. CJD causes failing memory, blindness, involuntary movement and coma, and kills 90 percent of patients within one year, according to the National Institute of Neurological Disorders and Stroke. The condition is similar to mad cow disease, but is not linked to beef consumption. The incubation period — before initial symptoms surface — can last years, the statement said. After the first sign of symptoms, most patients die within four months, it said The possibility of contracting the disease through surgical exposure is very remote, the hospital said.

Keyword: Prions
Link ID: 19234 - Posted: 02.11.2014

By Daniel Engber Drop a mouse in some water and white paint, and it will know just what to do. Mice can swim, by whipping their tails like a flagellum, but they don't like doing it; a mouse in a tub tries to find a way out. There's no need for training, or food pellets, or annoying electric shocks: To put a mouse through a water maze, you need only to build a little platform for it, hidden somewhere just beneath the surface. The mouse will try to find that platform without any encouragement. It's a setup that's so simple—and so useful in measuring an animal's capacity for learning and memory—it hardly seems like it would need inventing. But it took a cognitive neuroscientist at the University of St. Andrews in Scotland to come up with the tub-and-platform method. In 1979, Richard Morris built a heated pool about 4 feet and 3 inches in diameter, filled it with water and fresh milk, and then added a platform made of stones and drain piping. Within a few years, his method (designed for rats) had been adapted for smaller lab mice, and had made its way into rodent labs around the world. Now it's among the most widespread animal-testing protocols in all of biomedicine. Scientists plunge mice in murky water to test the effects of brain damage, or the functions of particular genes on learning, or the efficacy of new drugs for treating Alzheimer's. You can even buy a standard-issue "Morris Water Maze" direct from a lab-supply shop, along with specialized software for recording its results. That fact that so few of us would call a tub full of milk a “maze” only goes to show that rodent mazes aren't what they used to be. Early psychologists tempted rats with tricky blind alleys and wrong turns using contraptions built by hand, of wood and wire. © 2014 The Slate Group LLC.

Keyword: Learning & Memory
Link ID: 19233 - Posted: 02.11.2014

You probably saw dozens of people’s faces today, many more if you live in a city. You may not have been conscious of it, but you were subtly judging every one by its beauty. Your eyes are drawn to more attractive faces, and the almost inescapable result is that more attractive people have advantages in almost every aspect of life, from job interviews to prison sentencing. But what drives us to crave beauty? According to one theory, gazing upon beauty stimulates the brain’s μ-opioid receptors (MOR), thought to be a key part of our biochemical reward system. At least in rodents, stimulating or inhibiting MOR neurotransmission not only tweaks the animals’ appetite for sex or food, but also the strength of their preferences for particular foods or mates. Is our preference for pretty faces driven by the same biochemical reward circuit? To find out, researchers invited 30 heterosexual men to browse a series of female faces on a computer (one pictured). Each man received either a dose of the MOR-stimulating drug morphine, the opioid receptor–inhibiting drug naltrexone, or a placebo. The results, published today in Molecular Psychiatry, suggest that we seek out beautiful faces at least in part because our brains reward us. Not only did stimulating MOR neurotransmission cause men to linger longer on faces that they rated as more beautiful, but the beauty rating also became more extreme, with beautiful faces rated as even more attractive relative to the rest of the faces. Inhibiting MOR had the opposite effects. The findings are yet more evidence that our social interactions are strongly influenced by the invisible hand of evolution, pushing us to find attractive mates. But the question remains, how do we decide which face is attractive in the first place? © 2014 American Association for the Advancement of Science

Keyword: Sexual Behavior; Drug Abuse
Link ID: 19232 - Posted: 02.11.2014